The purpose of Core C - Gene Expression Analysis is to provide the projects with the highly specialized methodology required to: (1) extract high quality RNA from human and animal samples and perform quality control tests; (2) process RNA to produce high quality labeled cRNA for hybridization to the microarrays; (3) provide image capture and data mining software necessary for analyzing the vast amount of gene expression data generated by microarray technology; (4) perform data analysis tailored for each individual project; and (5) to quantify mRNA levels by TaqMan real time PCR for the genes selected by the microarray screen. The Gene Expression Analysis Core has extensive expertise in Affymetrix microarray data analysis using different methods and computational tools for data mining, particularly of samples obtained from the lungs of human volunteers by bronchoscopy/brushing, and bronchoalveolar lavage. The Core has at its disposal the Affymetrix GeneChip equipment, as well as state-of-the-art software packages that are available through the Weill Cornell Institute for Computational Biomedicine. TaqMan real-time RT-PCR for RNA quantitation is available through this Core, using high throughput 96 well Applied Biosystems 7500 and software to design specific primers for the genes of interest, as well as technical support and training to assist the investigators in each of the projects to carry out TaqMan analysis. The Core will devote equal resources to all five projects.